[The following excerpt is from John Piper's chapter in Recovering Biblical Manhood and Womanhood, entitled "A Vision of Biblical Complementarity: Manhood and Womanhood Defined According to the Bible." The entire chapter is available here.]

The tendency today is to stress the equality of men and women by minimizing the unique significance of our maleness or femaleness. But this depreciation of male and female personhood is a great loss. It is taking a tremendous toll on generations of young men and women who do not know what it means to be a man or a woman. Confusion over the meaning of sexual personhood today is epidemic. The consequence of this confusion is not a free and happy harmony among gender-free persons relating on the basis of abstract competencies. The consequence rather is more divorce, more homosexuality, more sexual abuse, more promiscuity, more social awkwardness, and more emotional distress and suicide that come with the loss of God-given identity.

It is a remarkable and telling observation that contemporary Christian feminists devote little attention to the definition of femininity and masculinity. Little help is being given to a son's question, "Dad, what does it mean to be a man and not a woman?" Or a daughter's question, "Mom, what does it mean to be a woman and not a man?" A lot of energy is being expended today minimizing the distinctions of manhood and womanhood. But we do not hear very often what manhood and womanhood should incline us to do. We are adrift in a sea of confusion over sexual roles. And life is not the better for it.

[However,] the Bible does not leave us in ignorance about the meaning of masculine and feminine personhood. God has not placed in us an all-pervasive and all-conditioning dimension of personhood and then hidden the meaning of our identity from us. He has shown us in Scripture the beauty of manhood and womanhood in complementary harmony. He has shown us the distortions and even horrors that sin has made of fallen manhood and womanhood. And he has shown us the way of redemption and healing through Christ.

To be sure, we see "through a glass dimly." Our knowledge is not perfect. We must be ever open to new light. But we are not so adrift as to have nothing to say to our generation about the meaning of manhood and womanhood and its implications for our relationships. Our understanding is that the Bible reveals the nature of masculinity and femininity by describing diverse responsibilities for man and woman while rooting these differing responsibilities in creation, not convention.

When the Bible teaches that men and women fulfill different roles in relation to each other, charging man with a unique leadership role, it bases this differentiation not on temporary cultural norms but on permanent facts of creation. This is seen in 1 Corinthians 11:3-16 (especially vv. 8-9, 14); Ephesians 5:21-33 (especially vv. 31-32); and 1 Timothy 2:11-14 (especially vv. 13-14).7 In the Bible, differentiated roles for men and women are never traced back to the fall of man and woman into sin. Rather, the foundation of this differentiation is traced back to the way things were in Eden before sin warped our relationships. Differentiated roles were corrupted, not created, by the fall. They were created by God.